End member and gas spring assembly including same

ABSTRACT

An end member ( 202 ) is dimensioned to engage an end of a flexible spring member ( 210 ) to at least partially form a gas spring assembly. The end member ( 202 ) includes an end member wall that has a longitudinal axis. The end member includes a securement wall portion ( 280 ) having an outer surface with a surface profile dimensioned to abuttingly engage the end of the flexible spring member ( 210 ). The surface profile includes a plurality of concave profile sections and a plurality of convex profile sections that are dimensioned to generate a progressively increasing compression force along at least a section of the securement wall portion ( 280 ). A gas spring assembly including such an end member ( 202 ) is included. A suspension system including one or more gas spring assemblies and a method of assembly are also included.

BACKGROUND

The subject matter of the present disclosure broadly relates to the artof gas spring devices and, more particularly, to an end member includinga progressively-varied crimp area as well as a gas spring assemblyincluding such an end member. A suspension system can include one ormore of such gas spring assemblies.

The subject matter of the present disclosure may find particularapplication and use in conjunction with components for wheeled vehicles,and will be shown and described herein with reference thereto. However,it is to be appreciated that the subject matter of the presentdisclosure is also amenable to use in other applications andenvironments, and that the specific uses shown and described herein aremerely exemplary. For example, the subject matter of the presentdisclosure could be used in connection with gas spring assemblies ofnon-wheeled vehicles, support structures, height adjusting systems andactuators associated with industrial machinery, components thereofand/or other such equipment. Accordingly, the subject matter of thepresent disclosure is not intended to be limited to use associated withgas spring suspension systems of wheeled vehicles.

Wheeled motor vehicles of most types and kinds include a sprung mass,such as a body or chassis, for example, and an unsprung mass, such astwo or more axles or other wheel-engaging members, for example, with asuspension system disposed therebetween. Typically, a suspension systemwill include a plurality of spring devices as well as a plurality ofdamping devices that together permit the sprung and unsprung masses ofthe vehicle to move in a somewhat controlled manner relative to oneanother. Movement of the sprung and unsprung masses toward one anotheris normally referred to in the art as jounce motion while movement ofthe sprung and unsprung masses away from one another is commonlyreferred to in the art as rebound motion.

In some cases, the spring devices can take the form of gas springassemblies that utilize pressurized gas as the working medium. Gasspring assemblies of various types, kinds and constructions are wellknown and commonly used. Typical gas spring assemblies can include aflexible wall that is secured between comparatively rigid end members. Awide variety of arrangements for securing the flexible wall on or alongan end member have been developed, and it is recognized that differentsecuring arrangements have different advantages, such as low cost,improved sealing or reliability, high strength and/or a capability ofdisassembly and/or repair, for example. Thus, different securingarrangements may be employed in different applications depending uponthe particular conditions under which the gas spring assembly isintended for use, such as applications during which elevated internalgas pressures, over-extension conditions and/or exposure to lowtemperatures may be experienced. In many cases, a different securingarrangement may be selected and used on each of the two different endmembers of a gas spring assembly.

Notwithstanding to overall success of known securing arrangements, it isbelieved desirable to develop end members for gas spring assemblies thatare capable of providing improved retention and/or securement of theflexible wall and overcoming disadvantages of known constructions whilepromoting relatively low costs of manufacture, ease of assembly and/orotherwise advancing the art of gas spring devices.

BRIEF SUMMARY

One example of an end member in accordance with the subject matter ofthe present disclosure that is dimensioned to engage an associatedflexible spring member of an associated gas spring assembly can includean end member wall having a longitudinal axis. The end member wall caninclude an end wall portion and a securement wall portion. The end wallportion can extend transverse to the axis and can include an outersurface that is dimensioned to abuttingly engage an associatedstructural component. The securement wall portion can extendlongitudinally from along the end wall portion and can include an outerperipheral extent with first, second and third grooves extendingradially inward into the securement wall portion from along the outerperipheral extent. The first, second and third grooves can be disposedin axially-spaced relation to one another such that a plurality ofridges can be formed along the securement wall portion. One of theplurality of ridges can be positioned between adjacent ones of thefirst, second and third grooves such that the plurality of ridges aredisposed in axially-spaced relation to one another. Each of the first,second and third grooves can have a groove depth with the groove depthsprogressively decreasing in an axial direction such that the first,second and third grooves are capable of generating avariable-compression wedge effect during abutting engagement with theassociated flexible spring member.

Another example of an end member in accordance with the subject matterof the present disclosure that is dimensioned to engage an associatedflexible spring member of an associated gas spring assembly can includean end member wall having a longitudinal axis. The end member wall caninclude an end wall portion and a securement wall portion. The end wallportion can extend transverse to the axis and can include an outersurface that is dimensioned to abuttingly engage an associatedstructural component. The securement wall portion can include an outersurface with a surface profile dimensioned to abuttingly engage theassociated flexible spring member. The surface profile can include atleast a first, second and third concave profile sections and at leastfirst and second convex profile sections interposed between adjacentones of the first, second and third concave profile sections. At leastthe first, second and third concave profile sections of the surfaceprofile can be dimensioned to generate a progressively increasingcompression force along at least a section of the longitudinal length ofthe securement wall portion upon application of a radially-in wordretention force applied approximately uniformly along the longitudinallength of the securement wall portion and biasing the associatedflexible spring member in a radially-inward direction.

One example of a gas spring assembly in accordance with the subjectmatter of the present disclosure can include a flexible spring memberhaving a longitudinal axis and including a flexible wall extendingperipherally about the longitudinal axis to at least partially define aspring chamber. The flexible wall can extend between a first end and asecond end that is spaced longitudinally from the first end. Theflexible wall can include an end wall portion disposed along at leastone of the first and second ends and can terminate at a flexible walledge. A first end member can be secured along the first end of theflexible spring member such that a substantially fluid-tight seal isformed therebetween. A second end member according to either of theforegoing paragraphs can be secured along the second end of the flexiblespring member such that a substantially fluid-tight seal is formedtherebetween. A retaining ring can extend about the axis and in abuttingengagement with the end wall portion of the flexible wall such that theend wall portion can be biased into engagement with at least alongitudinal section of the securement wall portion of the second andmember.

One example of a suspension system can include at least one gas springassembly according to the foregoing paragraph and a pressurized gassystem in fluid communication with the spring chamber of the at leastone gas spring assembly.

One example of a method of manufacturing a gas spring assembly inaccordance with the subject matter of the present disclosure can includeproviding a flexible spring member that has a longitudinal axis andincludes a flexible wall extending peripherally about the longitudinalaxis. The flexible wall can extend between a first end and a second endbut is spaced longitudinally from the first end. The flexible wall canalso include an end wall portion that is disposed along at least one ofthe first and second ends and terminates at a flexible wall edge. Themethod can also include providing a first end member and securing thefirst end member along the first end of the flexible spring member suchthat a substantially fluid-tight seal is formed therebetween. The methodcan further include providing a second and member according to either ofthe two above paragraphs and extending the end wall portion of theflexible wall along the securement wall portion of the second andmember. The method can also include providing a retaining ring thatextends peripherally about an axis and positioning the retaining ringadjacent the end wall portion of the flexible wall radially outward ofthe securement wall portion of the second and member. The method canfurther include deforming the retaining ring and a radially-inwarddirection such that the end wall portion of the flexible wall is biasedinto engagement with at least a longitudinal section of the securementwall portion of the second end member such that a substantiallyfluid-tight seal is formed therebetween.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of one example of a suspensionsystem of an associated vehicle including gas spring assemblies inaccordance with the subject matter of the present disclosure.

FIG. 2 is a side elevation view of one example of a gas spring assemblythat includes one example of an end member in accordance with thesubject matter of the present disclosure.

FIG. 3 is a cross-sectional side view of the gas spring assembly in FIG.2 taken from along line 3-3 in FIG. 2.

FIG. 4 is an enlarged, cross-sectional view of the portion of the gasspring assembly in FIGS. 2 and 3 identified as Detail 4 in FIG. 3.

FIG. 5 is an exploded view of the portion of the gas spring assembly inFIG. 4.

FIG. 6 is a further enlarged, cross-sectional view of the portion of theend member in FIGS. 4 and 5.

DETAILED DESCRIPTION

Turning now to the drawings, it is to be understood that the showingsare for purposes of illustrating examples of the subject matter of thepresent disclosure and are not intended to be limiting. Additionally, itwill be appreciated that the drawings are not to scale and that portionsof certain features and/or elements may be exaggerated for purposes ofclarity and/or ease of understanding.

FIG. 1 illustrates one example of a suspension system 100 disposedbetween a sprung mass, such as an associated vehicle body BDY, forexample, and an unsprung mass, such as an associated wheel WHL or anassociated axle AXL, for example, of an associated vehicle VHC. It willbe appreciated that any one or more of the components of the suspensionsystem can be operatively connected between the sprung and unsprungmasses of the associated vehicle in any suitable manner. Additionally,it will be appreciated that such a suspension system of the vehicle can,optionally, include a plurality of damping members, such as dampers DMP,for example, and that any such damping members can also be operativelyconnected between the sprung and unsprung masses of the associatedvehicle in any suitable manner.

The suspension system can also include a plurality of gas springassemblies supported between the sprung and unsprung masses of theassociated vehicle. In the arrangement shown in FIG. 1, suspensionsystem 100 includes four gas spring assemblies 102, one of which isdisposed toward each corner of the associated vehicle adjacent acorresponding wheel WHL. However, it will be appreciated that any othersuitable number of gas spring assemblies could alternately be used inany other configuration or arrangement. As shown in FIG. 1, gas springassemblies 102 are supported between axles AXL and body BDY ofassociated vehicle VHC. Additionally, it will be recognized that the gasspring assemblies shown and described in FIG. 1 (e.g., gas springassemblies 102) are illustrated as being of a rolling lobe-typeconstruction. It is to be understood, however, that gas springassemblies of other types, kinds and/or constructions could alternatelybe used.

Suspension system 100 also includes a pressurized gas system 104operatively associated with the gas spring assemblies for selectivelysupplying pressurized gas (e.g., air) thereto and selectivelytransferring pressurized gas therefrom. In the exemplary embodimentshown in FIG. 1, pressurized gas system 104 includes a pressurized gassource, such as a compressor 106, for example, for generatingpressurized air or other gases. A control device, such as a valveassembly 108, for example, is shown as being in communication withcompressor 106 and can be of any suitable configuration or arrangement.In the exemplary embodiment shown, valve assembly 108 includes a valveblock 110 with a plurality of valves 112 supported thereon. Valveassembly 108 can also optionally include a suitable exhaust, such as amuffler 114, for example, for venting pressurized gas from the system.Optionally, pressurized gas system 104 can also include a reservoir 116in fluid communication with the compressor and/or valve assembly 108 andsuitable for storing pressurized gas.

Valve assembly 108 can be in fluid communication with gas springassemblies 102 in any suitable manner, such as through suitable gastransfer lines 118, for example. As such, pressurized gas can beselectively transferred into and/or out of the gas spring assembliesthrough valve assembly 108 by selectively operating valves 112, such asto alter or maintain vehicle height at one or more corners of thevehicle, for example.

Suspension system 100 can also include a control system 120 that iscapable of communication with any one or more systems and/or components(not shown) of vehicle VHC and/or suspension system 100, such as forselective operation and/or control thereof. Control system 120 caninclude a controller or electronic control unit (ECU) 122communicatively coupled with compressor 106 and/or valve assembly 108,such as through a conductor or lead 124, for example, for selectiveoperation and control thereof, which can include supplying andexhausting pressurized gas to and/or from gas spring assemblies 102.Controller 122 can be of any suitable type, kind and/or configuration.

Control system 120 can also, optionally, include one or more height (ordistance) sensing devices 126, such as, for example, may be operativelyassociated with the gas spring assemblies and capable of outputting orotherwise generating data, signals and/or other communications having arelation to a height of the gas spring assemblies or a distance betweenother components of the vehicle. Height sensing devices 126 can be incommunication with ECU 122, which can receive the height or distancesignals therefrom. The height sensing devices can be in communicationwith ECU 122 in any suitable manner, such as through conductors or leads128, for example. Additionally, it will be appreciated that the heightsensing devices can be of any suitable type, kind and/or construction.

One example of a gas spring assembly 200 in accordance with the subjectmatter of the present disclosure, such as may be suitable for use as gasspring assemblies 102 in FIG. 1, for example, is shown in FIGS. 2 and 3.Gas spring assembly 200 can have a longitudinally-extending axis AX(FIG. 3) and can include one or more end members, such as an end member202 and an end member 204 that is spaced longitudinally from end member202. A flexible spring member 206 can extend peripherally around axis AXand can be secured between the end members in a substantiallyfluid-tight manner such that a spring chamber 208 (FIG. 3) is at leastpartially defined therebetween.

Flexible spring member 206 can be of any suitable size, shape,construction and/or configuration. Additionally, the flexible springmember can be of any type and/or kind, such as a rolling lobe-type orconvoluted bellows-type construction, for example. Flexible springmember 206 can include a flexible wall 210 that can be formed in anysuitable manner and from any suitable material or combination ofmaterials, such as by using one or more fabric-reinforced, elastomericplies or layers and/or one or more un-reinforced, elastomeric plies orlayers, for example. Typically, one or more fabric-reinforced,elastomeric plies and one or more un-reinforced, elastomeric plies willbe used together and formed from a common elastomeric material, such asa synthetic rubber, a natural rubber or a thermoplastic elastomer. Inother cases, however, a combination of two or more different materials,two or more compounds of similar materials, or two or more grades of thesame material could be used.

Flexible wall 210 can extend in a generally longitudinal directionbetween opposing ends 212 and 214. Additionally, flexible wall 210 caninclude an outer surface 216 and an inner surface 218, which can atleast partially define reservoir chamber 208. Additionally, asidentified in FIG. 5, flexible wall 210 can include an outer or coverply 220 that at least partially forms outer surface 216. Flexible wall210 can also include an inner or liner ply 222 that at least partiallyforms inner surface 218. In some cases, flexible wall 210 can furtherinclude one or more reinforcing plies 224 and 226 disposed between outerand inner surfaces 220 and 222. The one or more reinforcing plies can beof any suitable construction and/or configuration. For example, the oneor more reinforcing plies can include one or more lengths of filamentmaterial that are at least partially embedded therein. Additionally, itwill be appreciated that the one or more lengths of filament material,if provided, can be oriented in any suitable manner. As one example, theflexible wall can include at least one layer or ply with lengths offilament material oriented at one bias angle and at least one layer orply with lengths of filament material oriented at an equal but oppositebias angle.

Flexible spring member 206 can include at least one end wall sectionthat terminates at a flexible wall edge. In the arrangement shown inFIGS. 2-5, for example, flexible wall 210 of flexible spring member 206includes an end wall section (or portion) 228 (FIG. 5) disposed alongend 212 that terminates at a flexible wall edge 230. In some cases, theone or more reinforcing plies can be exposed along edge 230. In somecases, the flexible spring member can include another end wall section(or portion) along end 214 that terminates in a flexible wall edge withone or more of the reinforcing plies exposed therealong. In other cases,however, flexible spring member 206 can include a mounting bead 232disposed along one of ends of the flexible wall, such as end 214, forexample. In such cases, the mounting bead, if provided, can, optionally,include a reinforcing element, such as an endless, annular bead wire234, for example.

Gas spring assembly 200 can be disposed between associated sprung andunsprung masses of an associated vehicle in any suitable manner. Forexample, one end member can be operatively connected to the associatedsprung mass with the other end member disposed toward and operativelyconnected to the associated unsprung mass. In the arrangement shown inFIGS. 2-4, for example, end member 202 is secured along a first or upperstructural component USC, such as associated vehicle body BDY in FIG. 1,for example, and can be secured thereon in any suitable manner. Forexample, one or more securement devices, such as mounting studs 236, forexample, can be included along end member 202. In some cases, the one ormore securement devices (e.g., mounting studs 236) can project outwardlyfrom end member 202 and can be secured thereon in a suitable manner,such as, for example, by way of a flowed-material joint (not shown) or apress-fit connection (not identified). Additionally, such one or moresecurement devices can extend through mounting holes HLS in upperstructural component USC and receive one or more threaded nuts 238 (FIG.3) or other securement devices, for example. As an alternative to one ormore of mounting studs 236, one or more threaded passages (e.g., blindpassages and/or through passages) could be used in conjunction with acorresponding number of one or more threaded fasteners.

Additionally, a fluid communication port, such as a transfer passage 240(FIG. 3), for example, can optionally be provided to permit fluidcommunication with spring chamber 208, such as may be used fortransferring pressurized gas into and/or out of the spring chamber, forexample. In the exemplary embodiment shown, transfer passage 240 extendsthrough at least one of mounting studs 236 and is in fluid communicationwith spring chamber 208. It will be appreciated, however, that any othersuitable fluid communication arrangement could alternately be used.

End member 204 can be secured along a second or lower structuralcomponent LSC, such as an axle AXL in FIG. 1, for example, in anysuitable manner. As one example, lower structural component LSC couldinclude one or more mounting holes HLS extending therethrough. In suchcase, a mounting stud 242 could be operatively connected to end member204 and could extend through one of mounting holes HLS to receive acorresponding threaded nut 244, for example.

It will be appreciated that the one or more end members can be of anysuitable type, kind, construction and/or configuration, and can beoperatively connected or otherwise secured to the flexible spring memberin any suitable manner. In the exemplary arrangement shown in FIGS. 2-4,for example, end member 202 is of a type commonly referred to as a topcap or top plate and is secured to end 212 of flexible spring member 206using a retaining ring 246 that can be crimped or otherwiseradially-inwardly deformed to capture at least a portion of flexiblespring member 206 between the end member and the retaining ring. Endmember 204 is shown in the exemplary arrangement in FIGS. 2 and 3 asbeing of a type commonly referred to as a piston (or a roll-off piston)that has an outer surface 248 that abuttingly engages outer surface 216of flexible spring member 206 such that a rolling lobe 250 is formedtherealong. As gas spring assembly 200 is displaced between extended andcollapsed conditions, rolling lobe 250 is displaced along outer surface248 in a conventional manner.

As identified in FIG. 3, end member 204 extends generally between afirst or upper end 252 and a second or lower end 254. End member 204 caninclude a longitudinally-extending outer side wall 256 that extendsperipherally about axis AX and at least partially defines outer surface248. End member 204 can also include an end wall 258 disposed along end252 that extends generally transverse to axis AX. One example of aconnection between the flexible spring member and the end member isshown in FIG. 3 in which end member 204 includes an inner side wall 260that can extend longitudinally outward from end wall 258 in a directionaway from end 254. End 214 of flexible spring member 206 can be receivedalong inner side wall 260 such that a substantially fluid-tight seal isformed therebetween. It is to be understood, however, that thearrangement shown and described is merely exemplary and that any othersuitable construction and/or configuration can alternately be used.

End member 204 can also include a base wall 262 that is disposed alongend 254 of the end member and can be secured on or along outer side wall256 in any manner suitable for forming a substantially fluid-tightconnection, such as by using a flowed-material joint 264, for example.In some cases, mounting stud 242 can be operatively connected to basewall 262 in a manner suitable for forming a substantially fluid-tightseal therewith, such as by using a flowed-material joint 266, forexample. Additionally, end member 204 can include a chamber 268 that isformed therein, which can be in fluid communication with spring chamber208 or an external atmosphere EXT. In the exemplary arrangement shown,chamber 268 is at least partially defined by outer side wall 256, endwall 258, inner side wall 260 and base wall 262 and in fluidcommunication with spring chamber 208.

An end member in accordance with the subject matter of the presentdisclosure can include one or more walls having any number of one ormore wall portions. In the arrangement shown in FIGS. 2-6, for example,end member 202 can include an end member wall 270 that can include anend wall portion 272 that is disposed transverse to axis AX. End wallportion 272 can include an outer surface 274 and can optionally includean inner surface 276. In a preferred arrangement, at least a portion ofouter surface 274 can be approximately planar and can be dimensioned forsecurement on or along an associated structural component (e.g., upperstructural component USC). Additionally, end wall portion 272 can extendoutwardly to an outer peripheral edge 278.

End member wall 270 of end member 202 can also include a securement wallportion 280 that extends axially from along end wall portion 272 towarda distal edge 282. In some cases, the securement wall portion can bespaced radially inwardly from the outer peripheral edge such that ashoulder or shoulder wall portion can be formed along the end member. Inother cases, a shoulder wall portion 284 can project radially outwardbeyond outer peripheral edge 278 such that a shoulder surface 286 can beformed along end member 202. In some cases, shoulder surface 286 canface in a direction away from outer surface 274 and toward flexiblespring member 206. Additionally, or in the alternative, securement wallportion 280 can include a shoulder wall portion 288 that projects in aradially-outward direction adjacent distal edge 282 such that a shouldersurface 290 can be formed along end member 202. In some cases, shouldersurface 290 can face in a direction away from distal edge 282 and towardshoulder surface 286, if included.

As identified in FIG. 5, securement wall portion 280 can include aninside surface 292 and an outside surface 294 with at least the outsidesurface extending peripherally about axis AX. Additionally securementwall portion 280 can include any combination of one or more featuresand/or elements capable of generating a variable-compression wedgeeffect with the associated flexible wall (e.g., flexible wall 210) inaccordance with the subject matter of the present disclosure. As oneexample, securement wall portion 280 can include a plurality of groovesextending axis AX and at least partially around the outside surface ofthe securement wall portion. Additionally, securement wall portion 280can include a plurality of ridges that extend peripherally about axis AXand at least partially around the outside surface of the securement wallportion. The plurality of grooves can be positioned in spaced-apartrelation to one another such that one of the ridges is disposed betweenadjacent ones of the grooves. In some cases, one or more of the grooveand/or one or more of the ridges can have an endless, annular form.

In a preferred arrangement, the securement wall portion can include atleast three grooves having progressively variable geometric features,such as depth, width, spacing and/or cross-sectional shape. Terms suchas “progressive,” “progressively,” and the like broadly refer tovariations changing from a minimum size, shape, dimension, value,condition and/or characteristic to a corresponding maximum size, shape,dimension, value, condition and/or characteristic (or from a maximumsize, shape, dimension, value, condition and/or characteristic to aminimum size, shape, dimension, value, condition and/or characteristic)by sequentially increasing (or decreasing) the size, shape, dimension,value, condition and/or characteristic.

While it may be preferred that the progressively variable geometricfeature or features change from a minimum size, shape, dimension, value,condition and/or characteristic to a maximum size, shape, dimension,value, condition and/or characteristic in a substantially continuous,sequential manner, it will be appreciated that, in some cases, one ormore discontinuities can be included within such a progressivelyvariable sequence without departing from the subject matter of thepresent disclosure. For example, in some cases, progressively variablegeometric features can include two or more occurrences of a geometricfeature having a common size, shape, dimension, value, condition and/orcharacteristic. In a preferred arrangement, any such occurrences can bedisposed adjacent one another, such as are represented by the followingexemplary relationships:GF1≤GF2<GF3<GF4;GF1<GF2≤GF3<GF4; and,GF1>GF2≥GF3≥GF4≥GF5.It will be appreciated that in any of such cases, at least threegeometric features are included that define or otherwise establish a setof progressively variable geometric features that change from a minimumsize, shape, dimension, value, condition and/or characteristic to acorresponding maximum size, shape, dimension, value, condition and/orcharacteristic (or from a maximum size, shape, dimension, value,condition and/or characteristic to a minimum size, shape, dimension,value, condition and/or characteristic) in accordance with the subjectmatter of the present disclosure.

As identified in FIG. 5, securement wall portion 280 includes a groove296, a groove 298, a groove 300, a groove 302, and a groove 304 withgroove 296 disposed toward shoulder surface 286 and groove 304 disposedtoward shoulder surface 290. The grooves are disposed in axially-spacedrelation to one another such that securement wall portion 280 includes aridge 306 disposed between grooves 296 and 298, a ridge 308 disposedbetween grooves 298 and 300, a ridge 310 disposed between grooves 300and 302, and a ridge 312 disposed between grooves 302 and 304. In thearrangement shown in FIGS. 3-6, securement wall portion 280 includes anouter peripheral extent, which is represented by reference line OPE inFIG. 6, that is at least partially defined by ridge points 306P, 308P,310P and 312P of ridges 306, 308, 310 and 312, respectively. In apreferred arrangement, ridge points 306P-312P can be disposed inapproximate alignment with one another such that the reference linerepresenting outer peripheral extent OPE is at least approximatelyaligned with longitudinal axis AX.

As identified in FIG. 6, grooves 296-304 can have approximatecenterpoints, which are represented by item numbers 296C, 298C, 300C,302C and 304C, and a maximum depth (or a minimum cross-sectiondimension) at corresponding root points 296P, 298P, 300P, 302P and 304P.Additionally, grooves 296 and 304 are shown in FIG. 6 as having groovedepths, which are represented by reference dimensions 296D and 304D.While only two groove depths are identified in FIG. 6, it will berecognized and understood that grooves 298-302 also have correspondinggroove depths, which may be referred to herein by reference numbers298D, 300D and 302D.

Any suitable combination of grooves, ridges and/or other features can beused to form a variable-compression wedge effect engagement with an endwall section (e.g., end wall section 228) of an associated flexible wall(e.g., flexible wall 210). As one example of such a construction, threeor more of grooves 296-304 can have progressively decreasing (orincreasing) groove depths. As is identified in FIG. 6, root points296P-304P are shown as being progressively offset such that groove 296has groove depth 296D and groove 304 has groove depth 304D. Groove depth304D is shown as being less than groove depth 296D such that aprogressive offset is formed by the grooves, as is represented in FIG. 6by reference dimension OFS. As such, three or more of groove depths206D-304D can correspond to the relationship:296D>298D≥300D≥302D>304D.

Additionally, it will be appreciated that a root or reference line RLNextending between three or more of root points 296D-304D is disposed atan acute angle relative to longitudinal axis AX, outer peripheral extentOPE and/or a common centerline CCL of two or more of centerpoints296C-304C, which acute angle is represented in FIG. 6 by referencedimension AG1.

Securement wall portion 280 has a cross-sectional surface profile (notidentified) formed along outside surface 294. The surface profileincludes a plurality of curved or curvilinear profile sections that aredisposed in longitudinally-spaced relation to one another. The pluralityof profile sections can include two or more concave profile sections,such as can form grooves 296-304, for example, and two or more convexprofile sections, such as can form ridges 306-312, for example. It willbe appreciated that such concave profile sections and such convexprofile sections can be of any suitable size, shape and/orconfiguration. As one example, one or more of the concave and/or convexprofile sections can have an approximately semi-circular or otherwisearcuate shape. In such cases, the profile sections can have anapproximate centerpoint and a corresponding radius.

In the exemplary arrangement shown in FIGS. 3-6, the concave profilesections that can, in some cases, at least partially define grooves296-304 can have corresponding radii 296R, 298R, 300R, 302R and 304R,respectively. Radii 296R-304R can extend from corresponding centerpoints296C-304C and can vary progressively such that three or more of theradii 296R-304R correspond the relationship:296R>298R≥300R≥302R>304R.

In some cases, as discussed above, centerpoints 296C-304C can bedisposed in approximate alignment with one another. Under suchconditions, progressive variation of radii 296R-304R can result in rootpoints 296P-304P having the progressive offset discussed above and thecorresponding grooves having the progressive groove depth variationsdiscussed above, in accordance with the subject matter of the presentdisclosure.

Additionally, in the arrangement shown in FIGS. 3-6, the convex profilesections that can, in some cases, at least partially define ridges306-312 can have corresponding radii 306R, 308R, 310R and 312R,respectively. Radii 306R-312R can vary in size such that two or more ofthe radii correspond to the relationship:306R<308R≤310R<312R.

In some cases, radii 306R-312R can extend from correspondingcenterpoints (not shown) that can be disposed in progressive offsetrelation to one another such that ridge points 306P-312P can be disposedin approximate alignment with one another and can at least partiallydefine outer peripheral extent OPE of at least part of securement wallportion 280, such as has been discussed above.

Furthermore, or as an alternative, one or more other features orcharacteristics of the profile sections of the cross-sectional surfaceprofile of securement wall portion 280 can vary progressively inaccordance with the subject matter of the present disclosure. Forexample, the profile sections corresponding to grooves 296-304 and/orthe profile sections corresponding to ridges 306-312 can varyprogressively along the longitudinal length of securement wall portion280. As one example, the profile sections corresponding to grooves296-304 can have groove widths (or heights) 296W, 298W, 300W, 302W and304W. In some cases, groove widths 296W-304W can vary in size relativeto one another such that three or more of the groove widths correspondto the relationship:296W>298W≥300W≥302W>304W.

As another example, the profile sections corresponding to ridges 306-312can have ridge widths (or heights) 306W, 308W, 310W and 312W. In somecases, ridge widths 306W-312W can vary in size relative to one anothersuch that two or more of the ridge widths correspond to therelationship:306W<308W≤310W<312W.

As indicated above, end wall section 228 can be urged into and retainedin abutting engagement with securement wall section 280 in any mannersuitable for forming a substantially fluid-tight seal between end member202 and flexible spring member 206. As one example, gas spring assemblycan include retaining ring 246 that can take the form of an endlessannular ring that includes an inside surface 314, an outside surface 316spaced radially outward from the inside surface, and opposing edges 318and 320 that are spaced longitudinally from one another and can at leastpartially define an overall length of the retaining ring. In anuninstalled condition, retaining ring 246 can be dimensioned to extendperipherally about end wall section 228 and securement wall section 280.The retaining ring can be positioned along end wall section 228 andsecurement wall section 280. The retaining ring can then be crimped orotherwise deformed in a radially-inward direction such that a retentionforce is applied in the radially-inward direction to urge end wallsection 228 into abutting engagement with securement wall section 280.In a preferred arrangement, at least inside surface 314 of retainingring 246 can have an approximately flat cross-sectional profile suchthat the retaining ring can apply the retention force approximatelyuniformly along the longitudinal length of the securement wall portion,such as is represented by arrows FR in FIG. 4, for example. As a resultof the progressive surface profile along outside surface 294 ofsecurement wall portion 280, a progressively increasing compressionforce can be applied along end wall section 228 such that material ofthe end wall section can flow into and at least partially fill one ormore of grooves 296-304. In this manner, a variable-compression wedgeeffect can be generated along end wall section 228 of flexible wall 210,such as is represented by progressive length arrows FC1, FC2 and FC3 inFIG. 4, for example. In some cases, such an effect can provide improvedsealing and/or retention without the use of increased retention forcesacting in the radially-inward direction, which can undesirably deflectend member 202 and/or result in other undesired occurrences.

It will be appreciated that an end member in accordance with the subjectmatter of the present disclosure can be formed from any suitablematerial or combination of materials, such as one or more metalmaterials (e.g., steel, aluminum) and/or one or more polymericmaterials. Non-limiting examples of such one or more polymeric materialscan include fiber-reinforced polypropylene, fiber-reinforced polyamide,or unreinforced (i.e., relatively high-strength) thermoplastic (e.g.,polyester, polyethylene, polyamide, polyether or any combinationthereof), for example.

A height or distance sensing device 322, such as may be suitable for useas one of height sensing devices 126 in FIG. 1, for example, is,optionally, shown in FIG. 3 as being disposed within spring chamber 208along end member 202 and being secured thereto using suitable fasteners324. Height sensing device 322 can be of any suitable type, kind and/orconstruction, such as an ultrasonic sensor that transmits and receivesultrasonic waves WVS (FIG. 3), for example. Additionally, it will beappreciated that height sensing device 322 can be connected to othersystems and/or components of a vehicle suspension system in any suitablemanner. As shown in FIGS. 2 and 3, height sensing device 322 includes alead or connection 326 that can be used for such communication purposes,such as is indicated by leads 128 of control system 120 in FIG. 1, forexample.

As used herein with reference to certain features, elements, componentsand/or structures, numerical ordinals (e.g., first, second, third,fourth, etc.) may be used to denote different singles of a plurality orotherwise identify certain features, elements, components and/orstructures, and do not imply any order or sequence unless specificallydefined by the claim language. Additionally, the terms “transverse,” andthe like, are to be broadly interpreted. As such, the terms“transverse,” and the like, can include a wide range of relative angularorientations that include, but are not limited to, an approximatelyperpendicular angular orientation. Also, the terms “circumferential,”“circumferentially,” and the like, are to be broadly interpreted and caninclude, but are not limited to circular shapes and/or configurations.In this regard, the terms “circumferential,” “circumferentially,” andthe like, can be synonymous with terms such as “peripheral,”“peripherally,” and the like.

Furthermore, the phrase “flowed-material joint” and the like, if usedherein, are to be interpreted to include any joint or connection inwhich a liquid or otherwise flowable material (e.g., a melted metal orcombination of melted metals) is deposited or otherwise presentedbetween adjacent component parts and operative to form a fixed andsubstantially fluid-tight connection therebetween. Examples of processesthat can be used to form such a flowed-material joint include, withoutlimitation, welding processes, brazing processes and solderingprocesses. In such cases, one or more metal materials and/or alloys canbe used to form such a flowed-material joint, in addition to anymaterial from the component parts themselves. Another example of aprocess that can be used to form a flowed-material joint includesapplying, depositing or otherwise presenting an adhesive betweenadjacent component parts that is operative to form a fixed andsubstantially fluid-tight connection therebetween. In such case, it willbe appreciated that any suitable adhesive material or combination ofmaterials can be used, such as one-part and/or two-part epoxies, forexample.

Further still, the term “gas” is used herein to broadly refer to anygaseous or vaporous fluid. Most commonly, air is used as the workingmedium of gas spring devices, such as those described herein, as well assuspension systems and other components thereof. However, it will beunderstood that any suitable gaseous fluid could alternately be used.

It will be recognized that numerous different features and/or componentsare presented in the embodiments shown and described herein, and that noone embodiment may be specifically shown and described as including allsuch features and components. As such, it is to be understood that thesubject matter of the present disclosure is intended to encompass anyand all combinations of the different features and components that areshown and described herein, and, without limitation, that any suitablearrangement of features and components, in any combination, can be used.Thus it is to be distinctly understood that claims directed to any suchcombination of features and/or components, whether or not specificallyembodied herein, are intended to find support in the present disclosure.

Thus, while the subject matter of the present disclosure has beendescribed with reference to the foregoing embodiments and considerableemphasis has been placed herein on the structures and structuralinterrelationships between the component parts of the embodimentsdisclosed, it will be appreciated that other embodiments can be made andthat many changes can be made in the embodiments illustrated anddescribed without departing from the principles hereof. Obviously,modifications and alterations will occur to others upon reading andunderstanding the preceding detailed description. Accordingly, it is tobe distinctly understood that the foregoing descriptive matter is to beinterpreted merely as illustrative of the subject matter of the presentdisclosure and not as a limitation. As such, it is intended that thesubject matter of the present disclosure be construed as including allsuch modifications and alterations.

The invention claimed is:
 1. A gas spring assembly comprising: aflexible spring member having a longitudinal axis and including aflexible wall extending peripherally about said longitudinal axis to atleast partially define a spring chamber, said flexible wall extendingbetween a first end and a second end spaced longitudinally from saidfirst end, and said flexible wall including an end wall portion disposedalong at least one of said first and second ends and terminating at aflexible wall edge; a first end member secured along said first end ofsaid flexible spring member such that a substantially fluid-tight sealis formed therebetween; a second end member secured along said secondend of said flexible spring member such that a substantially fluid-tightseal is formed therebetween, said second end member including an endmember wall having a longitudinal axis, said end member wall includingan end wall portion and a securement wall portion with: said end wallportion extending transverse to said axis and including an outer surfacedimensioned to abuttingly engage an associated structural component;and, said securement wall portion extending longitudinally from alongsaid end wall portion and including an outer peripheral extent withfirst, second and third grooves extending radially inward into saidsecurement wall portion from along said outer peripheral extent, saidfirst, second and third grooves disposed in axially-spaced relation toone another such that a plurality of ridges are formed along saidsecurement wall portion with one of said plurality of ridges positionedbetween adjacent ones of said first, second and third grooves such thatsaid plurality of ridges are disposed in axially-spaced relation to oneanother, each of said first, second and third grooves having a groovedepth with said groove depths progressively decreasing in an axialdirection such that said first, second and third grooves are capable ofgenerating a variable-compression wedge effect during abuttingengagement with said flexible wall of said flexible spring member; and,a retaining ring extending peripherally about said axis and in abuttingengagement with said end wall portion of said flexible wall such thatsaid end wall portion of said flexible wall is biased into engagementwith at least a longitudinal section of said securement wall portion ofsaid second end member.
 2. A gas spring assembly according to claim 1,wherein said securement wall portion includes a fourth groove disposedadjacent said third groove in said axial direction and opposite saidsecond groove and said plurality of ridges include a ridge positionedbetween said third groove and said fourth groove.
 3. A gas springassembly according to claim 2, wherein said fourth groove has a groovedepth, and said groove depth of said fourth groove progressivelydecreases from said groove depth of said third groove.
 4. A gas springassembly according to claim 1, wherein said grooves have a curvilinearcross-sectional profile with a curvature and said curvature of saidgrooves progressively decrease in said axial direction.
 5. A gas springassembly according to claim 1, wherein said grooves have a curvilinearcross-sectional profile with at least a portion of two or more of saidprofiles being approximately semicircular and having a radius ofcurvature.
 6. A gas spring assembly according to claim 5, wherein saidradii of curvature of said two or more profiles progressively decreasein said axial direction.
 7. A gas spring assembly according to claim 1,wherein said grooves have a curvilinear cross-sectional profile with anapproximate centerpoint, and said approximate centerpoints are disposedin approximate alignment with one another in said axial direction.
 8. Agas spring assembly according to claim 1, wherein two or more ridges ofsaid plurality of ridges include a curvilinear cross-sectional profilehaving a curvature, and said curvature of said two or more ridgesprogressively increase in said axial direction.
 9. A gas spring assemblyaccording to claim 1, wherein two or more ridges of said plurality ofridges include a curvilinear cross-sectional profile with at least aportion of said profiles being approximately semicircular and having aradius of curvature.
 10. A gas spring assembly according to claim 9,wherein said radii of curvature of said profiles progressively increasein said axial direction.
 11. A gas spring assembly according to claim 1,wherein two or more of said ridges have a curvilinear cross-sectionalprofile with an approximate centerpoint, and said approximatecenterpoints are disposed in radially-offset relation to one another.12. A gas spring assembly comprising: a flexible spring member having alongitudinal axis and including a flexible wall extending peripherallyabout said longitudinal axis to at least partially define a springchamber, said flexible wall extending between a first end and a secondend spaced longitudinally from said first end, and said flexible wallincluding an end wall portion disposed along at least one of said firstand second ends and terminating at a flexible wall edge; an end membersecured along said first end of said flexible spring member such that asubstantially fluid-tight seal is formed therebetween, said end memberhaving a longitudinal axis and including an end member wall with an endwall portion and a securement wall portion; said end wall portionoriented transverse to said axis and including an outer surfacedimensioned to abuttingly engage an associated structural component;said securement wall portion extending axially from along said end wallportion and having a longitudinal length, said securement wall portionincluding an outer surface with a surface profile dimensioned toabuttingly engage said flexible wall of said flexible spring member,said surface profile including at least first, second and third concaveprofile sections and at least first and second convex profile sectionsinterposed between adjacent ones of said first, second and third concaveprofile sections, each of said concave profile sections having a maximumdepth at a root point with said maximum depths decreasing progressivelyfrom at least said first concave profile to said third concave profilesuch that said root points are disposed in offset relation to oneanother and a reference line extending through at least two of said rootpoints is disposed at an acute angle relative to said longitudinal axissuch that at least said first, second and third concave profile sectionsof said surface profile generate a progressively increasing compressionforce along at least a section of said longitudinal length of saidsecurement wall portion upon application of a retention force appliedapproximately uniformly along said longitudinal length of saidsecurement wall portion and bias said flexible wall of said flexiblespring member in a radially-inward direction; and, a retaining ringextending peripherally about said axis and in abutting engagement withsaid end wall portion of said flexible wall such that said end wallportion of said flexible wall is biased into engagement with at least alongitudinal section of said securement wall portion of said end member.13. A gas spring assembly according to claim 12, wherein said surfaceprofile includes a fourth concave profile section and a third convexprofile section interposed between said third concave profile sectionand said fourth concave profile section.
 14. A gas spring assemblyaccording to claim 13, wherein said surface profile includes a fifthconcave profile section and a fourth convex profile section interposedbetween said fourth concave profile section and said fifth concaveprofile section.
 15. A gas spring assembly according to claim 12,wherein said concave profile sections have a height in a longitudinaldirection with said heights decreasing progressively from at least saidfirst concave profile to said third concave profile.
 16. A gas springassembly according to claim 12, wherein said concave profile sectionshave a curvature and an approximate centerpoint with said curvaturesdecreasing progressively from at least said first concave profile tosaid third concave profile and with said approximate centerpoint of atleast said first, second and third concave profiles disposed inapproximate alignment with one another in said axial direction.
 17. Agas spring assembly according to claim 12, wherein said convex profilesections are disposed between adjacent ones of said concave profilesections and said convex sections have a maximum cross-sectionaldimension at a ridge point with said ridge points disposed inapproximate alignment with one another in said axial direction.
 18. Agas spring assembly according to claim 12, wherein said convex profilesections have a height in a longitudinal direction with said heightsincreasing progressively from at least said first convex profile to saidsecond concave profile.
 19. A gas spring assembly according to claim 12,wherein said end member is a first end member, and said gas springassembly further comprises a second end member secured along said secondend of said flexible spring member such that a substantially fluid-tightseal is formed therebetween.